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This brings up a question for me. With telescopes aperture rules. So 150mm aperture scope at F5 is going to be brighter than 100mm scope at F5 - right? Albeit at a narrower field of view.
So with camera lenses, even if 2 lenses are both F2.8 wouldn't the one with the wider aperture and same focal length be superior in collecting light.
I think the fact of aspherical lenses complicates the light gathering process as they are usually quite wide in aperture and thus must be collecting a lot of light and then bringing it to focus very rapidly so the focal length is short.
The downside is microlensed chips mean that light coming in at too sharp an angle will reduce sensitivity as the pixels often require light coming in within a 15 degree angle for their performance.
Anyone know more about this?
I may conduct an experiment my Nikon 14-24 front element is quite wide and seems to collect a lot of light. Would a narrower 14mm F2.8 collect less light even if the resulting optical result is 14mm F2.8???
Greg.
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